1. Field of the Invention
The present invention relates to a system and method for determining the phase envelope of a gas condensate.
2. Description of Related Art
Phase behavior studies of lean gas condensates are of growing importance in petroleum reservoir analysis. The dropout of condensate near a wellbore can significantly limit the recovery efficiency of hydrocarbons from the reservoir. Moreover, condensate yield at the surface of a well is a key parameter for determining the size of a liquid management system at the well. The dew point of a gas condensate is one of the most important thermo-physical properties of such fluids. However, the measurement of the dew point of a gas condensate is typically difficult to perform in conventional pressure-volume-temperature (PVT) systems. In such conventional systems, the subject fluid is injected into a pressure-balanced glass chamber. The dew point is detected by visually observing the formation of mist in the chamber as the pressure and temperature of the fluid are closely monitored. While improvements have been made to this basic PVT system, challenges stem from the difficulty in detecting and quantifying very small volumes of liquid in the gas. For example, dew point measurements become increasingly difficult as the liquid content of a gas decreases and other problems, such as liquid holdup on the chamber walls, occur. Conventional methods using PVT cells become challenged when measuring the dew point of fluids with less than about 1-2 percent liquid content by volume. Furthermore, conventional techniques often suffer from poor repeatability, poor reproducibility, and poor accuracy.
There are devices and methods for making measurements related to determining the phase envelope of a gas condensate that are well known in the art, however, considerable shortcomings remain.